JPH11166045A - Polyester ether film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyester ether film which is excellent in balance between heat resistance flexibility and strength, and excellent in transparency, fragrance retention, heat sealability and pinhole resistance. SOLUTION: This film is formed by molding a polyester ether comprising a dicarboxylic acid component mainly containing terephthalic acid and / or an ester derivative thereof and a diol component mainly containing tetramethylene glycol and polytetramethylene oxide glycol. A polyester ether film wherein the proportion of polytetramethylene oxide glycol is 1 to 30% by weight based on the polyester ether.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyester ether film, and more particularly, to a film comprising a copolymerized aromatic polyester ether.

[0002]

2. Description of the Related Art Polyethylene terephthalate film and polytetramethylene terephthalate film have heat resistance,
It has excellent electrical insulation, gas barrier properties, and fragrance retention properties, and is used for various applications.
There was a drawback that it was easily broken and a pinhole was easily generated. As a method of improving such a point, there is a method of blending with a flexible material such as a polyester elastomer, but in general, it is poor in compatibility and becomes white and opaque with a small amount of addition, and the intended purpose of softening is sufficient. There is a defect that is not achieved. Further, since the conventional terephthalate polyester film has a high melting point and poor heat sealing property, it is difficult to form a single film as a packaging material, and it is difficult to combine with a heat sealable resin such as polyethylene through an expensive adhesive. It must be a layer film.

As a method of improving the heat sealing property of a terephthalate-based polyester film, there is a method of using a polyester film copolymerized by combining a plurality of dicarboxylic acids other than terephthalic acid, tetramethylene glycol, and glycols other than ethylene glycol. Since it is an amorphous polyester, the gas barrier properties and the fragrance retention, which are the characteristics of the original terephthalate-based polyester film, are reduced and the flexibility is insufficient.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a polyester ether film which is excellent in balance between heat resistance, flexibility and strength, and is excellent in transparency, fragrance retention, heat sealability and pinhole resistance. It is in.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and its gist is to provide a dicarboxylic acid component containing terephthalic acid and / or an ester derivative thereof as a main component and a tetramethylene compound. A film formed by molding a polyester ether comprising a glycol and a diol component containing polytetramethylene oxide glycol as a main component, wherein the proportion of polytetramethylene oxide glycol residues in the polyester ether is 1 to 30% by weight. A polyester ether film characterized in that:

Hereinafter, the present invention will be described in detail. As the dicarboxylic acid component in the present invention, terephthalic acid and / or an ester derivative thereof is used as a main component. The proportion of terephthalic acid and its ester derivative in the dicarboxylic acid component is preferably from 70 to 100 mol%, more preferably from 90 to 100 mol%.

As components other than terephthalic acid and its ester derivative, isophthalic acid, phthalic acid, 2,6-
Naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, bis (4,4′-carboxyphenyl) methane,
Anthracene dicarboxylic acid, aromatic dicarboxylic acid such as 4,4'-diphenyl ether dicarboxylic acid, alicyclic dicarboxylic acid such as 1,4-cyclohexanedicarboxylic acid, 4,4'-dicyclohexyl dicarboxylic acid, adipic acid,
Examples include aliphatic dicarboxylic acids such as sebacic acid, azelaic acid, and dimer acid and ester derivatives thereof. The proportion of the aromatic dicarboxylic acid in the dicarboxylic acid component is preferably at least 70 mol%, more preferably at least 90 mol%, from the viewpoint of mechanical properties, gas barrier properties and heat resistance.

[0008] The glycol component in the present invention includes:
The main component is tetramethylene glycol and polytetramethylene oxide glycol. The proportion of tetramethylene glycol and polytetramethylene oxide glycol in the glycol component is preferably 70 to 10
0 mol%, more preferably 90 to 100 mol%.

The components other than tetramethylene glycol and polytetramethylene oxide glycol include aliphatic or alicyclic diols having 2 to 20 carbon atoms, bisphenol derivatives and the like. Specific examples include ethylene glycol, propylene glycol, and the like. 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, decamethylene glycol, cyclohexane dimethanol, 4,4′-dicyclohexylhydroxymethane, 4,4′-dicyclohexylhydroxypropane, ethylene oxide addition diol of bisphenol A , Polyethylene oxide glycol, polypropylene oxide glycol and mixtures thereof. Further, triols such as glycerin and trimethylolpropane can be used.

[0010] The polyester ether in the present invention is
It comprises a dicarboxylic acid component containing terephthalic acid and / or an ester derivative thereof as a main component and a diol component containing tetramethylene glycol and polytetramethylene oxide glycol as main components.

The proportion of polytetramethylene oxide glycol residues in the polyester ether is from 1 to 30% by weight. When the proportion of the polytetramethylene oxide glycol residue is less than 1% by weight, the heat sealability is insufficient, and when it exceeds 30% by weight, the heat resistance is reduced, and the adhesiveness of the film becomes remarkably difficult to form a film. . The proportion of the polytetramethylene oxide glycol residue in the polyester ether is preferably 3 to 25% by weight, more preferably 5 to 20% by weight.

The number average molecular weight of the polytetramethylene oxide glycol in the present invention is preferably from 300 to 300.
5,000. If the number average molecular weight is less than 300, the softening is insufficient, and if it exceeds 5,000, the heat resistance tends to decrease. The number average molecular weight of polytetramethylene oxide glycol is more preferably from 500 to 2,500, and most preferably from 700 to 2,000. The number average molecular weight of the polytetramethylene oxide glycol was measured by reacting an excess of phthalic anhydride with a polytetramethylene oxide glycol sample and calculating the hydroxyl equivalent per 1 g of the sample by quantifying the remaining phthalic anhydride. The number average molecular weight was determined.

The melting point of the polyester ether in the present invention is a melting peak temperature measured by a DSC method at a heating rate of 20 ° C./min.
5 ° C. The melt viscosity of the polyester ether in the present invention is preferably from 1,000 to 20,000 poise when measured at 250 ° C. and a shear rate of 100 sec ⁻¹ . If the melt viscosity is too low, the extrudability of the film decreases, and the flexibility becomes insufficient. If the melt viscosity is too high, film formation becomes difficult. The melt viscosity of the polyester ether is more preferably from 2,000 to 15,000 poise, measured at 250 ° C. and a shear rate of 100 sec ⁻¹ .

As mechanical properties of polyester ether
Indicates bending on 1/4 "test piece specified by ASTM, D790
The elastic modulus is preferably 2,500 to 18,000 kg /
cm ^TwoAnd more preferably from 3,000 to 15,000.
0kg / cm^TwoAnd a 25μ thick unstretched film
The measured Young's modulus is preferably 2,000 to 16,0.
00kg / cm^TwoAnd more preferably 3,000 to
10,000kg / cm^TwoIt is.

The method for producing the polyester ether includes a conventional condensation polymerization method well known to those skilled in the art. For example, tetramethylene glycol and polytetramethylene oxide glycol are added at a predetermined ratio to the dimethyl ester of terephthalic acid, and a catalyst such as an alcoholate, chloride or oxide of tin, titanium, zinc, manganese, or germanium is added. Below, about 150-250 ° C
And a methanol is distilled off by a transesterification reaction. Then, at a reduced pressure of 10 mmHg or less, 200
Polycondensation can be performed by heating and polycondensing at ~ 280 ° C. In this reaction step, a heat stabilizer and the like can be added.

At this time, polytetramethylene oxide glycol may be added first, followed by transesterification, followed by addition of tetramethylene glycol, followed by transesterification and polycondensation. In addition, terephthalic acid can be directly polycondensed with tetramethylene glycol or polytetramethylene oxide glycol. Further, the resin pellets of the polyester ether obtained by melt polycondensation as described above are heat-treated at a high temperature of 170 to 210 ° C. under an inert gas stream to obtain a polyester ether having a higher molecular weight by a so-called solid state polymerization method. Can also.

The polyester ether film of the present invention comprises a dicarboxylic acid component mainly composed of terephthalic acid or an ester derivative thereof and a diol component mainly composed of tetramethylene glycol and polytetramethylene oxide glycol. It is a film formed by molding a polyester ether in which the ratio of methylene oxide glycol is 1 to 30% by weight based on the polyester ether.

The polyester ether film of the present invention is preferably a non-oriented film or a uniaxially or biaxially oriented stretched film. The thickness of the polyester ether film is preferably from 5 to 300 µm, more preferably from 10 to 250 µm.

The polyester ether film of the present invention contains, as other components, antioxidants such as phosphite compounds and hindered phenols, heat stabilizers, ultraviolet absorbers such as benzotriazole compounds and benzophenone compounds, and hindered amine compounds. Light stabilizers such as compounds can be added. Further, a nucleating agent, a plasticizer, a coloring agent, and the like can be added. Further, a lubricity-imparting agent, a lubricant and the like for improving workability at the time of film formation and post-processing of the film can be appropriately added as necessary. Examples of the slipperiness imparting agent include inorganic fine particles such as silica, talc, kaolin, and calcium carbonate; organic polymer fine particles such as poly (meth) acrylic resin, polystyrene resin, and polytetrafluoroethylene resin;
Organic polymer crosslinked fine particles are exemplified. The particle size of the slipperiness imparting agent is preferably 0.1 to 10 μm.

As a method for producing the polyester ether film of the present invention, for example, a film is formed using polyester ether by using a T-die film forming machine or an inflation film forming machine. In case of T-die film forming machine, cylinder temperature 220
Extrude at ~ 260 ° C and roll into a film at 5-90 ° C. At this time, the film slip property can be improved by using a mat-processed chill roll, and a corona treatment can be performed to perform an adhesion-improving surface treatment for a laminated material. When obtaining a stretched film, the film is uniaxially stretched, sequentially stretched or simultaneously biaxially stretched in an atmosphere from room temperature to about 70 ° C, and heat-set at 180 to 220 ° C to obtain a uniaxially stretched film or a biaxially stretched film.

In the case of molding by the inflation method, the molten resin is extruded from a circular die at the same cylinder temperature setting as described above, blow-up at a blow-up ratio of about 1.2 to 1.7 by air cooling or water cooling, and then cooled. And take up the film. In the case of the polyester ether film of the present invention, the water cooling method is more suitable. In order to obtain a multilayer film with another resin, a known co-extrusion method can be applied regardless of a molding method.

[0022]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples unless it exceeds the gist thereof. The evaluation methods of the films in the examples and comparative examples are as follows. (1) Measurement of Young's modulus, tensile strength and tensile elongation: A test piece having a length of 100 mm was cut out from a film in a machine direction (referred to as MD) and a direction perpendicular to the machine direction (referred to as TD) in a width of 15 mm, and ASTM D 23 ° C according to -882
The measurement was performed at a pulling speed of 200 mm / min at a distance between the lower chucks of 50 mm.

(2) Measurement of heat seal strength and elongation at break: A film having a width of 250 mm and a length of 200 mm was cut out, half-folded in the 200 mm direction, and about 20 mm from the bent side.
mm was sealed with a hot plate heat sealer having a width of 300 mm and a seal width of 10 mm at 210 ° C. under a pressure of 2 kg / cm 2 for 1 second. From this, a test piece was cut out to have a width of 15 mm, and the heat sealing strength was measured at a pulling speed of 200 mm / min. The strength was set to the maximum value, and the breaking elongation was determined. The mode of failure in this test was also observed.

(3) Measurement of haze: A test piece of 60 × 60 mm was taken out and cut out at five locations in the width direction, and the haze was measured with a haze meter to obtain an average value. (4) Flex resistance evaluation: 23 by Mil-B-131C method
A pinhole test was performed at 500 ° C. and 65% RH for 500 cycles. (5) Measurement of melt viscosity: 250 ° C., shear rate 100 sec
It was measured at c- ¹ . (6) Measurement of flexural modulus: ASTM, 1 of D790 regulation
/ 4 "test piece.

Reference Example 1 (Synthesis example of polyester ether (a)) 801 parts by weight of dimethyl terephthalate, 435 parts by weight of 1,4-tetramethylene glycol were placed in a reactor equipped with a stirrer, a thermometer, a gas replacement port, and a distillation column. , Number average molecular weight about 100
0.3 parts by weight of tetrabutyl titanate as a catalyst was charged into 100 parts by weight of polytetramethylene oxide glycol 0, and the temperature was raised to 200 ° C. over 40 minutes after purging with nitrogen, and kept at 200 ° C. for 2 hours to distill methanol. I let it. Next, 1.7 parts by weight of pentaerythrityl-tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] and 0.1 part of sodium hypophosphite monohydrate were added to the reactor. 07 parts by weight, followed by 24
The temperature was raised to 0 ° C. over 60 minutes, and at the same time, the pressure of the reaction system was gradually reduced to 3 Torr or less, and the temperature was further maintained for 2 hours. Thereafter, the polymer was extruded into water from a die hole, scraped and cut to obtain a pellet. The obtained pellet was dried at 80 ° C. to a water content of 100 ppm or less, and then heat-treated at 200 ° C. in an inert gas atmosphere to obtain a polyester ether (a). The ratio of the polytetramethylene oxide glycol residue in the obtained polyester ether (a) was 10% by weight, and the melt viscosity was 3,800.
Poise, melting point 222 ° C, flexural modulus 8,400kg
/ Cm ² .

Reference Example 2 (Synthesis Example of Polyester Ether (b)) Dimethyl terephthalate 507 was prepared in the same manner as in Reference Example 1.
Polyester ether (b) was obtained by using 272 parts by weight of 1,4-butanediol and 100 parts by weight of polytetramethylene oxide glycol having a number average molecular weight of about 1,000. The ratio of the polytetramethylene oxide glycol residue in the obtained polyester ether (b) was 15% by weight, the melt viscosity was 3,500 poise,
Melting point: 219 ° C, flexural modulus: 5,400 kg / cm ²
Met.

Reference Example 3 (Synthesis Example of Polyester Ether (c)) In the same manner as in Reference Example 1, dimethyl terephthalate 360
Polyester ether (c) was obtained using 190 parts by weight of 1,4-butanediol and 100 parts by weight of polytetramethylene oxide glycol having a number average molecular weight of about 1,000. The ratio of the polytetramethylene oxide glycol residue in the obtained polyester ether (c) was 20% by weight, the melt viscosity was 3,000 poise,
Melting point: 216 ° C., flexural modulus: 4,400 kg / cm ²
Met.

REFERENCE EXAMPLE 4 (Synthesis Example of Polyester Ether (d)) In the same manner as in Reference Example 1, dimethyl terephthalate 14
Polyester ether (d) was obtained using 0.2 parts by weight, 92.8 parts by weight of 1,4-butanediol and 100 parts by weight of polytetramethylene oxide glycol having a number average molecular weight of about 1,000. The ratio of the polytetramethylene oxide glycol residue in the obtained polyester ether (d) was 40% by weight, and the melt viscosity was 2,800.
Poise, melting point 196 ° C, flexural modulus 1,000k
g / cm ² .

Example 1 Polyester ether (a)
After drying at 120 ° C. for 8 hours, the diameter was 40 mm and L / D = 2.
Kneading and extruding at 250 ° C. using an extruder T
Casting roll temperature at 30 ° C, thickness 25μ at 25 ° C
m of polyester ether film A was obtained. Various evaluations were performed using the film having substantially no molecular orientation. The results are shown in Table 1. The failure mode at the time of the heat seal strength measurement was a film break at a portion other than the heat seal portion, indicating a good seal.

Example 2 Polyester ether (b)
And a film was formed with a T-die in the same manner as in Example 1, and the thickness was 2
A polyester ether film B of 5 μm was obtained, and various evaluations were performed as in Example-1. The results are shown in Table 1. The failure mode at the time of the heat seal strength measurement was a film break at a portion other than the heat seal portion, indicating a good seal. Example 3 Using a polyester ether (c), a film was formed with a T-die in the same manner as in Example 1 to obtain a polyester ether film C having a thickness of 25 μm, and various evaluations were performed as in Example 1. . The results are shown in Table 1. The failure mode at the time of the heat seal strength measurement was a film break at a portion other than the heat seal portion, indicating a good seal.

Example 4 Polyester ether (c)
After forming a film having a thickness of 95 μm with a T-die in the same manner as in Example 1 using
The film was simultaneously biaxially stretched at a magnification of 2.5 and then heat-set at 220 ° C. for 1 minute to obtain a biaxially stretched polyester ether film D having a thickness of 15 μm. For the obtained film,
Various evaluations were performed in the same manner as in Example 1. The results are shown in Table 1. The failure mode at the time of the heat seal strength measurement was a film break at a portion other than the heat seal portion, indicating a good seal.

Comparative Example 1 A 25 μm-thick PBT film was formed using a T-die in the same manner as in Example 1 except that the kneading extrusion temperature was 270 ° C. and the T-die temperature was 260 ° C. using polytetramethylene terephthalate. Various evaluations were performed in the same manner as in Example 1. The results are shown in Table 1. The fracture mode at the time of heat seal strength measurement showed brittle fracture at the end of the heat seal. The flexural modulus of polytetramethylene terephthalate was 24,000 kg / cm ² .

Comparative Example 2 A biaxially stretched PET film having a thickness of 15 μm was formed in the same manner as in Example 4 except that the film was stretched in an atmosphere of 50 ° C. using polyethylene terephthalate. went. Table 1 shows the results.
It was shown to. The flexural modulus of polyethylene terephthalate was 28,000 kg / cm ² . [Comparative Example 3] A film having a thickness of 25 µm was formed using a T-die in the same manner as in Example 1 except that the kneading extrusion temperature was 230 ° C and the T-die temperature was 260 ° C, using polyester ether (d). However, the adhesiveness was so strong that a film could not be formed.

[0034]

[Table 1]

Example 5 (Evaluation of fragrance retention) Polyester ether film A having a thickness of 25 μm used in Example 1, a PBT film having a thickness of 25 μm used in Comparative Example 1, and a low density polyethylene film having a thickness of 25 μm (Hereinafter, referred to as an LDPE film) and 15
A packaging material of 0 × 150 mm was prepared, and various samples shown in Table 2 were filled and sealed, and the fragrance retention was evaluated by a sensory test one week later. The case where the fragrance retention was extremely excellent was evaluated as 5, the case where it was excellent, 4 when it was excellent, 2 when it was slightly inferior, and 1 when it was inferior.

[0036]

[Table 2]

[0037]

The polyester ether film of the present invention is excellent in balance between flexibility and strength, and excellent in transparency, fragrance retention, heat sealability and pinhole resistance, heat resistance, low temperature toughness, and electrical insulation. Excellent in heat resistance and gas barrier properties, insulating films, various food packaging films, heat resistant films for microwave ovens, heat shrinkable labels, stretch films, protective films for stationery, tools, machine parts, etc., and various laminates requiring flexibility Films and tubes (toothpaste, wax, etc.), toiletries, cosmetics, fragrance-retaining films for medical applications (paste packaging),
It is useful for various applications such as non-adsorptive paper pack films for juices and alcoholic beverages.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI B29L 7:00 C08L 67:00 (72) Inventor Tatsuhiko Hatakeyama 5-6-2 Higashi-Hachiman, Hiratsuka-shi, Kanagawa Prefecture Mitsubishi Engineering-Plastics Co., Ltd. Inside the company technology center

Claims (7)

[Claims] 1. A film formed by molding a polyester ether comprising a dicarboxylic acid component mainly containing terephthalic acid and / or an ester derivative thereof and a diol component mainly containing tetramethylene glycol and polytetramethylene oxide glycol. A polyester ether film, wherein the proportion of polytetramethylene oxide glycol residues in the polyester ether is 1 to 30% by weight. 2. The polyester ether film according to claim 1, wherein the number average molecular weight of the polytetramethylene oxide glycol is from 500 to 6,000. 3. The polyester ether having a melting point of 200 to 200.
The polyester ether film according to claim 1, wherein the temperature is 225 ° C. 4. 4. The polyester ether has a melt viscosity of 1,000 when measured at a temperature of 250 ° C. and a shear rate of 100 sec ^−1.
2. The method according to claim 1, wherein the pressure is about 20,000 poise.
4. The polyester ether film according to any one of items 1 to 3. 5. The polyester ether ASTM, D7
The flexural modulus of a 90-specified 1/4 "specimen is 2,50.
Polyester ether film according to any one of claims 1 to 4, characterized in that a 0~18,000kg / cm ^2. 6. The polyester ether film according to claim 1, wherein the thickness of the polyester ether film is 5 to 300 μm. 7. The polyester ether film according to claim 1, wherein the polyester ether film is a non-oriented film or a stretched film uniaxially or biaxially oriented.